%0 Journal Article
%A Hashemi, Rohallah
%A Nassar, Nashaat N.
%A Almao, Pedro Pereira
%D 2015
%T In Situ Upgrading of Athabasca Bitumen
Using Multimetallic Ultradispersed Nanocatalysts in an Oil Sands Packed-Bed
Column: Part 2. Solid Analysis and Gaseous Product Distribution
%U https://acs.figshare.com/articles/journal_contribution/_i_In_Situ_i_Upgrading_of_Athabasca_Bitumen_Using_Multimetallic_Ultradispersed_Nanocatalysts_in_an_Oil_Sands_Packed_Bed_Column_Part_2_Solid_Analysis_and_Gaseous_Product_Distribution/2029053
%R 10.1021/ef401719n.s001
%2 https://acs.figshare.com/ndownloader/files/3600360
%K scanning electron microscopy
%K CO 2 emission reduction
%K Multimetallic Ultradispersed Nanocatalysts
%K trimetallic nanocatalysts
%K reaction severity
%K coke precursor gases
%K Gaseous Product DistributionThermal
%K presence
%K CO 2 emission
%K media
%K UD
%K ESEM
%X Thermal
cracking of Athabasca bitumen was carried out in an oilsand
packed-bed column, in the presence and absence of in situ prepared trimetallic nanocatalysts at a pressure of 3.5 MPa, residence
time of 36 h, and temperatures of 320 and 340 °C. In this part
of the study, the effects of reaction severity (time and temperature)
as well as the presence of nanocatalysts in packed media on solid
and gaseous products were investigated. Results showed that the presence
of trimetallic nanocatalysts enhanced the hydrogenation reactions
and, consequently, led to significant reduction of coke formation
(51.3%) and CO2 emission reduction. Further, the analysis
of the gaseous products and deposited solids confirmed the previous
findings reported in part 1 (10.1021/ef401716h) of this study. The accumulative volume of coke precursor gases,
such as ethylene and propylene, increased with the reaction severity.
However, reaction severity has no significant effect on the atomic
metallic ratios (metal/total metal) of the employed trimetallic nanocatalysts,
which clearly demonstrates the stability of injected ultradispersed
(UD) nanocatalysts (metal/total metal: Mo, 0.6267; Ni, 0.1808; and
W, 0.1924) in the porous media at high pressure and temperature. Nonetheless,
aggregation of nanocatalysts inside the porous media was observed
and graphically demonstrated by environmental scanning electron microscopy
(ESEM) images. Overall, the presence of trimetallic nanocatalysts
in porous media not just enhanced bitumen upgrading but also improved
the produced liquid quality and reduced the coke content as well as
CO2 emission by 50%.
%I ACS Publications